A Field Study of Thermal Comfort in Outdoor and Semi-outdoor Environments in a Humid Subtropical Climate City

Very few studies exist on the outdoor thermal environment and thermal comfort impact of a semi-outdoor environment-under a piloti-in a humid subtropical climate city. Subjective data was collected using questionnaires both in a square and under a piloti during June and July 2011 in Wuhan. The aims were to obtain a better understanding of human thermal comfort response while outdoors and to clarify the effect of piloti on thermal comfort in a humid subtropical climate city. It was found that mean radiant temperature (MRT) plays a more important role than air temperature in the subjective response of people to the outdoor thermal environment. The relationship between the standard effective temperature (SET*) and thermal sensation vote (TSV) was clarified, and the neutral SET* was calculated as being about 24.8 degrees C. Being under a piloti has a notable impact, reducing the heat effect by ameliorating the microclimate and enhancing human thermal comfort outdoors. When the maximum air temperature exceeded 35 degrees C during daytime, the SET* decreased by 9 degrees C under the piloti in a humid subtropical climate city relative to that in a nearby square, and the acceptance rate of the outdoor thermal environment under the piloti was more than twice that in the square.